fbdev: simplify logic in fbdev_read_packet()

Signed-off-by: Stefano Sabatini <stefano.sabatini-lala@poste.it>

libavdevice/fbdev.c

@@ -189,22 +189,20 @@ static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
         fbdev->time_frame = av_gettime();
 
     /* wait based on the frame rate */
-    while (1) {
-        curtime = av_gettime();
-        delay = fbdev->time_frame - curtime;
-        av_dlog(avctx,
-                "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
-                fbdev->time_frame, curtime, delay);
-        if (delay <= 0) {
-            fbdev->time_frame += INT64_C(1000000) * av_q2d(fbdev->time_base);
-            break;
-        }
+    curtime = av_gettime();
+    delay = fbdev->time_frame - curtime;
+    av_dlog(avctx,
+            "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
+            fbdev->time_frame, curtime, delay);
+    if (delay > 0) {
         if (avctx->flags & AVFMT_FLAG_NONBLOCK)
             return AVERROR(EAGAIN);
         ts.tv_sec  =  delay / 1000000;
         ts.tv_nsec = (delay % 1000000) * 1000;
         while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
     }
+    /* compute the time of the next frame */
+    fbdev->time_frame += INT64_C(1000000) * av_q2d(fbdev->time_base);
 
     if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
         return ret;